With another month of nearly flawless behaviour, I am going to have to say that SolarDock is done.

Sure there is some weirdness when turning on and off where some postcaps don't "hear" the NRF and so don't turn on or off in response to the broadcast message. This appears to be fairly random and clears up on it's own without any intervention from me.

Last weekend, we sat out on the dock for a couple of hours one evening with all of the lights on, and it worked without issue, the only effect was that it took a little longer to reach full charge the following day.

This weekend I happened to be on the dock around the time that the sun was most on axis. I took a look at the charge controller and saw this...

I have also been running the lights until 0100 each night which is around 5 hours at this time of year. The battery voltage has been over 12.5v for the entire week, including the night after a poor charging (cloudy) day on two separate occasions. I have yet to see how it behaves with several consecutive days of poor charging, but I am confident it'll be OK

Back on November 6 I wrote that I was seeing 1.1A coming from the panel. This weekend I was out on the dock in the morning and I looked at the charge controller, the panel was at the time producing 4A!

This was not at peak production time so I think the peak is even higher, I may never know as I don't have the time to site and watch it. I think at some point hook I may up my serial DVM and record the output against time. I can use the panel fuse holder for this.

About a week ago I decided that before I installed the tracker and really invested time into it, I would try a couple of ideas. This involved two related items, more battery capacity and swapping out the repaired panel for the never broken one.

Soon after my last post at a routine eye exam, they found a minor issue, however it has meant that I have needed eye drops in the interim. Soldering small SMD packages with one eye dilated was challenging.

I got past that, and have been working the tracker firmware. Initially the device would not program, I think this is due to the opamp output holding the pin at the wrong level, I solved the issue by lifting the opamp pins in question.I don't know if this has broken the board by lifting the pads too, but it does now program consistently.

As I mentioned in the previous post, I was going to design and build a solar tracker. As time has gone by, this has become more necessary.

When I first set the panel angle I was getting great performance (fairly consistent 1.1A off the panel). Now, 3 weeks later, not so much as the angles are all wrong again, and I am back to getting about 20 minutes of runtime in the evening.

So, what a difference that made!

After changing the angle on Sunday, we had a couple of fairly cloudy days, so there was no opportunity to see what a difference it had made. That was until today.

After the last post, I monitored the charging system and battery more closely to see if changing the angle made any difference...

It had not.

As mentioned I thought I had got the angle wrong again, so I decided I needed to make adjustments. I used the principle that something pointing directly at the sun casts its shadow directly below itself (it looks like there is no shadow at all). My tri-square has an edge that is nominally square so it will stand perpendicular to the surface it is on.

So the battery is not getting charged during the day, again. As the battery is new, I decided that it must be either the charge controller, or the panel is at the wrong angle.

Last weekend I took my weather station of the dock post and put it on the chimney on top of the house. This should give me significantly more accurate measurements especially when it comes to wind speed and direction.


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